Alternating current alarm



March 26, 1935. A. KVAAL 1,995,457

" ALTERNATING CURE NT ALARM Filed Dec. 26, 1930 being supported by means 'ture, which is made in ne ted Ma 26,1935

ALTERNATING murmur (isle, Norway, or A/ S Eeklr Bureau, Oslo, Norway a plic nt December 26,1930, Serial No; tosses Norway ember 31, 1929 The present invention relates to an alternating current alarm, wherein the armature is suspended in a-simple manner.

. An essentialieature resides in the armature of two pair oi knife easy tilting of the armathe formof a plate conedges enabling a very stituting the counter-parts of the said edges.

justable head 12, a clamping washer 14 The armature support is made as a, spring having a longish aperture, through which projects an excentric portion of a turnable screw. When this is turned, the said spring is raised or lowered thereby adjusting the armature vertically relatively to the electromagnet the armature is retained in contact with one of the magnet cores either by spring actionor by a magnetic' momentum produced by a permanent magnet forming part of the alarm. 4

The invention is illustrated in the accompanying drawing, wherein Fig. 1 is a side view, partly in section, showing the alarm magnets with the Fig. 1. Fig. 3 is a perspective view ture' suspension drawn to a larger scale.

'1 and 2 are the magnet coils, 3 and 4 the two legs of a horse-shoe shaped core. From the end portion of the core a vertical lug 5 is stamped out serving to carry the armature support 6, 7, 8. This consists of and an intermediate non-magnetic spring 7. These parts may be connected together by a rivet9. Y

The support is suspended on tion of the stem of a screw 11 having an adnut 13 and a springy enabling a turning oi the screw by means-oi the 12 without any loosening of the nut'13 from the screw.

Atits lower part the plate at 15 enabling the central spring '1 to be bent laterally. The, lowermost portion of the spring 'Iis extended into a T shape as-indicated at 1'1. Thereby the lateral extensions of the portion 1'I.may constitute lower 8 is cut out as shown knife edges 21 serving to carry the armature plate 24. This is an important feature of the invention enabling a very easy tilting motion or the The springlaterally extended portions 18, 19 or such a shape as to constitute at their servinstoretainthe coils1and2in The extensions .18, 191mm plate to position.-

cores. When at rest two magnetic steel plates 6,8

an excentric porend portion 16 ot the '1 forms lateral provided at 1 their lower-ends with edges 22161 a supporting at their lower part upper knifeedges 23 for the armature plate 24, be seen, supported tiltingly by two pairs of knife edges 21 and 23.

provided with guidingpins 25, 26 projecting down 5 through holes 27,28 made '24. From the armature plate there are stamped out central transverse edges 21 have its tilting contact. 32 which co-operates with supported by the clapper stem 31 made integral the supporting serted without When the spring sition the armature that it may tilt freely.

In order to obtain a perfect tilting action of the armature, the

with each sary that by a turning of the ture. supportfi, '7, ,8 be adjusted vertically only. For this purpose engages ,the support through a longish hole 34 in edges thus alignment the parts 6, "I, 8. ltwill "be see alarm described may pressing. Consequently,

lecture and may spring port'on 16 'may be in such a position be introduced under the lugs .29,

The tilting of its simple What is claime mounting portion the armature and support enables a very easy motion of the armatureeasily adjusted and construction.

1. An alternating current alarm comprising magnet cores, electromagnetic coils thereon, a tiltable magnet armature operative relation with said cores, an armaturee meals? tiltin which is consequently, as will The extensions 18, 19 are also in the armature plate lugs 29, 30 upon which the The clapper the bell cups 33 is 10 side through is tilted fliculty below is returned to its vertical powill be secured on the knife .kniieedges 21 and 23 are in other. Further, it is neces-" screw 11 the armathe excentric screw portion 10 that the most parts of .the be formed by stamping or it will'be cheap in manube easily assembled, because the bent to the side and Moreover, the alarm-may be will operate perfectly in spite d is, 40

disposed below and inmounting memberdisposed in said cores and having a spring extending at right angles to capable of being bent laterally so that the armature can-be fitted thereove'r and ions disposed in provided with armature-supporting edges, porflxed relation to the cores and provided with counter-edges in alignment with the said supporting formed on one tiltinsly with the edges, the armature bein so side with; portions cooperating. 5 supporting edg s and on the opv v i (I posite side with portionscooperating tiltingly with tine-supporting edges, p t ns isp e fix d the counter-edges that the two sets of edges and relation h cores n p v d wi h unt rcooperating portions form in combination a ed8e8 in alignment i the Said PD hE d tions to allow assembly of the armature on the the two sets of edges cooperating Portions spring in operative position. form in combination a pivotal support for the electromagnetic coils, a permanent magnet in Posed f Shaped as to receive seid-spl'ihgimouhtfixed relation to the coils, atiltablemagnet arma- 1118 Demon, When the latte! bent laterally,

to the permanent magnet ha 5- An alternating current alarm Comprising spring portion extending at right angles to the electromagnet coils, cores therefor,at iltable magarmature and capable of being bent laterally so net armature diepe'sed l w in Operative provided with counter-edges in alignment with said Permanent m and extending at right the said supporting edges, the armature being so angles. to the n having spring opposite side 'with portions cooperating tiltingly. 'edgesl'mmme in fixed relation the m an opening so disposed and .shaped as to operating tiltingly with the supporting edgesand receive said spring mounting portion, when the h P s with Portions ceepemtihg latter is bent laterally, under the armature portutmgly wlth e emmte edges that the two sets tions to allow assembly of the armature on theedges and cooperating Portions form spring in operative position blnation a pivotal support for the armature, the

3. .An alternating current alarm comprising 3 an Welling dispesed and shaped electromagnetic coils, a tiltable magnet armaas to reqelve said spring mounting P o when and having a spring portion extending at right Ewing edjfl-ceht opelhhg haped as to rethereover and provided with armature-supportassembly of the alvmature Oh t Spring in 0D- 8 edges, portions disposed in fixed relation to the msitmnl 45 cores and provided with 'counter-edgesin alignalternating current alarm mp in t t t said supporting edges the arms; electromagnet coils, cores for the same, a tiltable so ing tiltingly with the counter-edges that the two k spring member extendinz right anele 58 tion, when the latter is bent literalb, under t middle extension, upwardly directed armature ,4. An alternating current alarmcomprising h r e te i s in lnment witliftlie magnet cores, electromagnetic coils thereon, a tti ed daca. 88 011' the armature cosllnporting and'mounting member llfrgnged in as to receive linden-the im' the [edge carrying fixed relation to'said-cores-and having a sprin portioi ot the'middle extension, when bent later- 7 mounting portion extending at right angle; to ally, to allow assembly or the ture on the .86 the armature and capable '01 being bent lateral]; spring member inoperative position:

'mvided.withmtelidelmfmingm- Amim'rxvm l0 2. An alternating current alarm: comprising armature, the letter having an Opening 80 dis-- 2 tions disposed in fixed relation to the cores and sprihe' member diemsed between the seetiehs of ture disposed below and in operative relation with the latter is n laterally under e armature and on the opposite side with pommzcoopemb tions and attachingbetween them an armature sets 01 edges and cooperating portions iorm in wte t armature filmed with three n-1- combination a pivotal support for the armature, wm'dly 91' 01mins ex-tensmnsmemmdle h tiltablemagnet armature and in we l zhr with laidmiddle extension. operative relation with i'laid rmaturedges and having andi ing 0 ha d 

